Alina has 3/2 hours to complete her homework. She should divide her 3/2 hours by the 3 assignments to determine how much time she will spend on each assignment. This turns out to be 1/2 hours, or 30 minutes, on each assignment. 3/2 hours is the same thing as 90 minutes, so this answer makes sense. We want the time to be divided by the number of assignments, not vice versa.